As well known by those skilled in the art, in providing oil-type circuit interrupters it has been common practice to provide interrupter grid structures formed by stacking a plurality of suitably-configured plate elements. As typical of such prior-art structures, reference may be made to U.S. Pat. No. 3,646,296, issued Feb. 29, 1972, to Robert L. Hess and Gerald D. Summers, and assigned to the assignee of the instant application. Such a grid structure provides oil pockets and side lateral vent passages, all having the function of creating turbulence and providing an exhausting lateral venting action to assist in extinguishing the arc, which is established and lengthened within the grid structure by the downward opening separating movement of a rod-shaped movable contact away from an upper-disposed stationary finger contact structure.
As descriptive of additional prior-art constructions, reference may also be made to U.S. Pat. No. 3,356,811, issued Dec. 5, 1967, to George B. Cushing and Frank L. Reese, and also assigned to the assignee of the present invention.